The skids have been put under fears by cyclists that reflective road markings are a hazard.
The death of cyclist Sam Raphael in Wellington last year sparked complaints that the thermoplastic markings - which contain glass beads to reflect headlights at night and in bad weather -were a danger because the raised surface deflected bike tyres and the surface was slippery.
However, Transit New Zealand has run tests which apparently show that the lines are not as hazardous as thought.
Transit has, nevertheless, changed the dimensions of the lines, which it has been using since 1992, to ensure they are no more than 4mm high, instead of 6mm, and less slippery.
As part of the $80,000 study, cyclists rode over lines in a Lower Hutt car park hundreds of times at various speeds and in the wet. Only a few times did they feel unsafe, said Transit's engineering policy manager, Dr John Donbavand.
One cyclist taking part, Geoff Campbell, of Cycling New Zealand, said he felt uneasy beforehand and was surprised at the results.
The test results would be put on the association's website.
"It's not to say you should be blase. You should proceed with caution, but people do not need to have the fear they had previously," he said.
Dr Donbavand said Transit had not changed the depth of the lines because they were unsafe.
"There was no definitive proof ... but working with the cyclists we felt 'why not allay their fears?'"
